Latch assembly

ABSTRACT

A latch assembly for latching two components comprising a support member arranged to be attached, in use, to a first component to be latched. 
     A lever member is pivotally attached to the support member at a first pivot point, and an engaging member is pivotally attached to the support member at a second pivot point. The engaging member is arranged to be moved, by movement of the lever member, from a position in which it urges a second component out of engagement with the first component to a position in which it engages with a second component to be latched to draw the second component into engagement with the first component and latch the components.

BACKGROUND OF THE INVENTION

There are many applications in which it is required to latch twocomponents into engagement with one another. In many such applicationsit is difficult for a user carrying out the latching to assertsufficient force to ensure sufficient engagement or disengagement of thetwo components for the required purpose.

A good example of such a situation is the latching of an electricalcircuit board to a housing, in which it is required that, when the boardand housing are in engagement, the engagement be such that goodelectrical contact is made between the board and the housing. Giventhat, in many situations, such components are in a confined region withrestricted access, it is difficult for a user to ensure good engagementunless force is applied to sections of the board or housing that are notdesigned to withstand such force.

Furthermore, once such components are in engagement, it is often verydifficult to remove them from engagement with one another without,again, requiring force to be applied to regions that are not designed toreceive such force.

SUMMARY OF THE INVENTION

According to the present invention there is provided a latch assemblyfor latching two components, the assembly comprising:

a support member arranged to be attached, in use, to a first componentto be latched;

a lever member pivotally attached to the support member at a first pivotpoint; and

an engaging member pivotally attached to the support member at a secondpivot point and arranged to be moved, by movement of the lever member,from a position in which it urges a second component out of engagementwith the first component to a position in which it engages with a secondcomponent to be latched to draw the second component into engagementwith the first component and latch the components.

The engaging member may have a pin or slot formed therein, the pin orslot engaging, in use, with a slot or pin on the lever member.

If a slot and pin arrangement is provided the position of the slot andpin relative to the first and second pivot points may be selected suchthat, when the latch assembly is in a latched position, the latch isbiased to remain in that position.

The first pivot point may be closer than the second pivot point to theengaging surface of the engaging member to provide good mechanicaladvantage.

The lever member may be arranged so that it can be folded into a storageposition.

One example of the present invention will now be described withreference to the accompanying drawings,

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a latch assembly according to an example of thepresent invention in an engaged and latched posit;

FIG. 2 is a side view of the latch assembly of FIG. 1 in an latcheddis-engaging position;

FIG. 3 is plan view of the latch assembly of FIG. 1; and

FIGS. 4A and 4B are plan and side views of a second example of thepresent invention in an engaged latched position.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a support block 3 for a latch assembly according tothe invention is attached to a first component 1 which is to be latchedto a second component 2. Pivotally supported on the support block 3 is alever member 4. The lever member 4 is pivotally supported upon thesupport block 3 by pins 5. Also pivotally attached to the support block3 is an engaging member 6. The engaging member 6 is pivotally attachedto the support block 3 by a pin 7. An engaging portion 8 is formed onone end of the engaging member 6. A slot or slots 9 are formed in thelever member 4 and a pin or pins 10, attached to engaging member 6, areretained therein.

In operation, the latch assembly is initially in unlatched position(FIG. 2) and a user pivots the lever member 4. The retaining slots 10 inthe pivot member 4 pivot the engaging member 6 via the pins 9. Theengaging portion 8 of the engaging member 6 engages with the secondcomponent to be latched 2. The second component to be latched 2 is thendrawn into engagement with the first component to be latched 1. Thelever member 4 can finally be pivoted no further and is biased into thelatch position by the relative positions of the pins 5, 7 and pin andslot arrangement 9,10. When disengaging the two components to be latched1,2, the lever member 4 is pivoted in the opposite direction and afurther section of the engaging portion 8 urges the two components 1,2out of engagement.

FIG. 4 shows a second example of the present invention, in whichcomponents correspond to those in the example of FIG. 1 have identicalnumbering. In this example, the lever member 4 is arranged so that ithas a releasable latch 11 formed thereon. The lever member 4 is formedfrom two components pivotally attached to one another by a pin 12. Thereleasable latch 11 allows the lever member to be folded around the pin12 when the releasable latch 11 is activated. This means that, when thelatch is in a latched position, the lever member 4 can be moved into aposition in which it does not impinge upon anything attached to thesurface of the first component 1.

The present invention, whilst enabling strong and reliable latching oftwo components, also allows for simple disengagement of the twocomponents when required. Furthermore, it has a minimum number of simplecomponents, making it cheap and easy to manufacture. In addition, it hasa low profile which means that a series of latched components can bestacked one upon another in close relationship.

What is claimed is:
 1. A latch assembly for latching two components, theassembly comprising: a support member arranged to latchably engage, inuse, to a first component; a lever member pivotally attached to thesupport member at a first pivot point; and an engaging member having anengaging surface, the engaging member being pivotally attached to thesupport member at a second pivot point and arranged to be moved, bymovement of the lever member, from a position in which the engagingsurface urges a second component out of engagement with the firstcomponent to a position in which the engaging surface engages with thesecond component to be latched to draw the second component intoengagement with the first component and latch the components, whereinthe first pivot point is closer than the second pivot point to theengaging surface of the engaging member.
 2. An assembly according toclaim 1, wherein the engaging member has a pin formed therein, the pinengaging, in use, with a slot on the lever member.
 3. An assemblyaccording to claim 2, wherein the position of the slot and pin relativeto the first and second pivot points may be selected such that, when thelatch assembly is in a latched position, the latch is biased to remainin that position.
 4. An assembly according to claim 1, wherein the levermember is arranged so that it can be folded into a storage position. 5.An assembly according to claim 1, wherein the engaging member has a slotformed therein, the slot engaging, in use, with a pin on the levermember.
 6. An assembly according to claim 5, wherein the position of theslot and pin relative to the first and second pivot points may beselected such that, when the latch assembly is in a latched position,the latch is biased to remain in that position.